Shampoo

"The best advice I can give my clients is to not overdo the shampoo," advises Elaine Mitchell, creative director for Sassoon Salon in New York City. There are many telltale signs of product overuse including flaking, limpness and dandruff. "One client in particular came in asking why her hair is always stuck with static and flyaways," which Mitchell says is a cue to ask how much and how often she's shampooing.

A good bottle of shampoo goes a long way and emulsifying it in your hands before applying to the hair will stretch the product even further. To measure it out, imagine the size and volume of one raspberry.

That's all the shampoo you need for one wash. Seriously!TODAY

Conditioner

Yes, it is possible to overdo it on the conditioner! Squeeze out a blackberry-sized dollop for short- to mid-length hair and double it for longer tresses. The key is to focus on the ends, unless your roots and scalp feel dry, and to ensure that you're rinsing it completely before scurrying out of the shower. If you're having a tough time getting volume at the roots, under-rinsed conditioner might be to blame.

Just a small scoop of conditioner will do the trick. For long-haired ladies, try doubling that size.TODAY

Serum and oil

While they're often miracle-workers, serums and oils can also cause a hairy situation if used incorrectly. (We had to.) One false move and it looks like you haven't showered in weeks. Go easy: Start with the size of a hazelnut and coat the ends by raking fingers through hair. Then, you can always add more if needed!

Be careful with serum or oil! A little goes a long way.TODAY

Styling cream

Love that effortless, just-rolled-out-of-bed look? Styling cream might be the key to achieving it. But be wary about how much you use.

"Instead of looking freshly washed, your hair winds up weighed down, limp and perhaps even greasy," Michell explains. And styling creams can cause product build-up over time that makes hair more difficult to style. To use it correctly, begin styling with a pumpkin seed's worth of product and work up from there.

When it comes to styling cream, start small. You can always add more!TODAY

Wax and pomade

Go overboard with waxes or pomades and you'll need to jump back into the shower!

"For some hair-care products, overdoing it will just result in the need to rewash and start over again, especially with waxes since hair will become unmanageable," says Wilson. You'll barely be able to get a wide-tooth comb through it! Waxes and pomades also have a tendency to cast a matte texture on hair. So if you're looking for more shine, that's even more reason to portion accordingly!

We recommend scooping out just a coffee bean's worth and working in more as needed.

Mousse

Yes, mousse is still a worthwhile product to add to your arsenal. It can add texture, volume and body to otherwise limp hair. But use too much and you'll start heading into crunchy, '80s territory. To keep hair looking fresh and modern, use about a tomato's size of mousse. No double dipping!

Moose can still come in handy! Just stick to a tomato-sized portion to avoid crunchy, '80s-style curls.TODAY